Ok i have the factory system blasting on the highway, got home and thought my back speacker was blown beacuse there was a weird noise comeing out of it. got a new speacker and still got the same noise. so its got to be the amp right? now i took the back speaker out and use the amp for the ones in the door. My question is

1) is it really the amp thats blown or is it the radio

2) now that i have two speaker, i want a amp that i can plug both of them in, can i plug any amp in with the factory radio or does it have to be a bose

need help now, i really need some bass